Electrical treating apparatus, especially for sterilization



oct. 11, 193s. E s SWTH l2,132,703

ELECTRICAL TREATENG APPARATUS ESPECIALLY FOR STERILIZATIONl 4Original Filed Oct. 8, 1934 4 Sheets-Sheet l INVENTOR FRH/VKUN J Sfr/7W ab, was +m ATTORNEYS Oct. l1, 1938.

F. S. SMITH ELECTRICAL TREATING APPARATUS ESPECIALLY FCE,sTEMmzAIIoN 4 sheets-'sheet 2 Original Filed Oct. 8, ,1934

F. S. SMITH oct. '11, 193s.

ELECTRICAL TREATING APPARATUSl ESPECIALLY`FOR STERILIZATION original Filedoct. 8, 1934 4 Sheets-Sheet 3 @Mza WQQMMQ ATTORNEYSV Oct. l1, 1938. F. s. SMITH ELECTRICAL TREA'IING` APPARATUS ESPECIALLY FOR STERILIZATION Original Filed Oct* 8, 1934 4 Sheets-Shes?I 4 INVENTOR f/P//v/rz/A/ ff/77( ATTORNEYS Patented oci. 11, 1938 UNITED STATES PATENT OFFICE Franklin S. Smith, New Haven, Conn.

, Application October 8, 1934, Serial No. 747,437

Renewed October 17, 1936 29 Claims.

This invention relates to apparatus which is particularly adapted for destroying insect life in foodand other products.

One of the objects of this invention is to provide4 apparatus which may be used for treating materials and which is admirably adapted for use in subjecting food and other products that contains insects and/or they eggs, larvae and pupae ,thereof to thoroughly practical and eflicient treatment for destroying such insect life. Another object is to provide apparatus for electrically destroying such life in a thoroughly dependable, rapid and efcient manner. Another object is to provide apparatus of the above-mentioned character for destroying insect life in food and other products in a rapid and dependable manner without harming the product undergoing treatment. Another object is to provide apparatus of the above-mentioned character which is simple and compact in constructionand thorough and dependable in operation. Another object is to provide a compact, simple, inexpensive and reliable electrode structure and -driving means therefor, for use in and coaction with apparatus of the above-mentioned character. Another object is to provide a dependable and eicientelectrode construction capable of efficient and dependable action in practical use. Another object is to provide an electrode tip or electrode construction in which dependable and reliable control of the discharge therefrom is achieved. Other objects will bejin part obvious or in part pointed out hereinafter.

This application is a continuationin part of my co-pending application Serial No. 627,291,- led August 2, 1932, renewed December 27, 1933, issued October 9, 1934, as Patent No 1,975,805.

The invention accordinglyconsists in the features of construction, combinations of elements, and arrangements of parts as will be exemplified in the structure to be hereinafter described andthe scope of the application of which will be in dicated in the following claims.

In the accompanying drawings in which are shown several of the various possible embodiv ments of my invention;

Figure lis a front elevation of a possible form of apparatus embodying therein certain features of my invention, for electrically destroying insect life in food products, or the like, certain parts being in Figure 1 shown diagrammatically; I

Figure 2 is a front elevation, on an enlarged scale, partly in central vertical section, of an electrode structure and drive therefor, as may be employed in the apparatus of Figure 1;

(ci. 21-1o2) Figure 3 is a bottom plan view, as seen from the bottom in Figure 2, of the electrode structure of the latter;

Figure 4 is a detached vertical sectional view, on a larger scale, of one of the electrode mem- 5 bers of Figures 2 and 3, and others, being more specically a vertical sectional view on an enlarged scale, as seen along the line 4-4 of Figure 2;

rFigure 5 is an elevation, as seen from the top of Figure 4;

Figure 6 is a detached elevation of the package or product carrying or conveying apparatus and related parts, being more specifically a plan view, as seen along the line 6-6 of Figure 1;

Figure 7 is a vertical sectional view, on an enlarged scale, as seen along the line 1--1 of Figure 1, showing an illustrative form of means for 'coacting with the rotating electrodes of the apparatus; 20

1 Figures 8 and 9 are diagrammatic or fragmen-` tary plan views indicating diagrammatically certain actions on the product or packages to be treated by the electrode structure of Figures 2 and 3; 25

Figure 10' is a diagrammatic plan view of the vstator and rotor and windings of 'the induction motors that drive the electrodes, showing certain interrelations of these parts; and

Figure 11 is afragmentary side elevation of the stator per se of Figure 10.

Similar reference characters refer to similar parts throughout the several views in the drawings.

Referring to the drawings and more particu# larly to Figure 1 thereof, there is indicated diagrammatically a suitable frame I provided at its respective ends with appropriate pairs of vertical standards II and I2 in which are suitably journaled the shafts I3 and I4 respectively of the drums I and I6. About the drums I5 and I6 extends a suitable conveyor belt I1 preferably made of asbestos, canvas, cotton material, or the like.

One of the drums, such as the drum I6, is suitably driven and I have diagrammatically indicated a motor I8 connected to the drum I6 by any suitable transmission diagrammatically indicated at I9 for driving the drum I6 and for thus transmitting motion to the conveyor belt I1. The direction of the drive is preferably such that a tension is put on the upper half of the belt and, as viewed in Figure 1, the motion will be from left toright or illustratively from A to B. Illustratively the rate of drive of the pulley or drum I6 may besuch that the movement of the is a limiting rate of drive but that the belt may be driven at any other suitable speed.

The belt il is adapted to receive at its lefte hand end, as at point A, the material, goods or articles to be sterilized and thus to transport vthe goods in a direction toward the 'right and to discharge them at the right-hand end of the belt, as at the point B. Any suitable means, not shown, may be utilized to feed the articles on to the belt and to receive them after they have beenl discharged therefrom.

Beneath the article-carrying portion of the belt i7 and extending lengthwise thereof is a plate-like member 20 (see also Figures 6 and 7) preferably of a width somewhat greater than the Width of the conveyor belt I'i. The member 20 aids in preventing the sag of the belt il under its load and insures the passage of the material, goods, or articles to be treated along the indicated and prescribed path.

Plate member 26 is made of any suitable solid dielectric material, preferably Pyrex glass, and it extends in a direction lengthwise of the belt throughout a suitable distance. Plate 20 is preferably supported by a pair of laterally spaced and lengthwise extending insulating beams Zia and 22a (see also Figure 6) secured in any suitable manner at their respective ends to the frame I6, being illustratively and preferably secured to the standrads H and I2. aremade of any appropriate or suitable solid dielectric material such, fpr example, as laminated Bakelite, and are preferably given such cross-sectional dimensions as to withstand the vertical stresses to which they are subjected. The cross-section may be, for example, L-shaped or it may be square tubing. Any suitable means may be utilized to secure the supportingplate 2t to its associated insulating beams 2te and 22a.

If desired, the insulating beams 2l and 22*l may be mechanically reinforced by the respective side members 2l and 22. 'I'hese side members are preferably made of a sheet-like solid dielectric material, sueh as laminated Bakelite. The side members 2i and 22 are preferably secured along their upper edges tofth'e beams 2l'i and 22a and thus form downwardly extending anges that o'er substantial resistance to bending because of the load carried thereby,

The upper portion of the frame lil serves to support framework structures generally shown (Figure 1) at 23 and 2d which in conjunction with a longitudinally extending beam 82 serves to support a plurality of electrode structures, illustratively two in number, and generally indicated in Figure 1 at S and T. 'I'he electrode structures S and T are merely diagrammatically indicated 1n Figure 1 and theyl may take any of the various forms, about to be described and the details of which are shown in enlarged scale in other views of the drawings. It is therefore to be understood that any of the electrode structures later herein described in detail may be employed in the apparatus oft-Figure 1 in which they are to be considered as representedl by the 'diagrammatic rep,- resentations thereof at rious possible forms of .electrode structures, that shown in Figures 2 and 3 may rst be considered. u

Referring, then, more particularly to Figure 2, there is shown an electrode structure comprising an upper rotatable housing 80 preferably made of a, suitable electrically conducting material Beams 2te and 22H' S and T. Of these vaiS/M . which may be readily cast, such, for example, as

aluminum. The housingl 3U has an upper generally cylindrical portion and a lower outwardly and downwardly extending skirt portion Mi. The skirt portion il is`preferably provided with a circle of evenly spaced holes, each of which is adapted to receive an electrode -member M2. The various electrode members H2, M21), M26, H201, etc. are thus arranged in a circle and they are preferably inclined with their lowermost tip portions trailing from their upper portions when the housing 80 is rotated about its central or vertical axis. These electrode members are preferably of identical construction and in Figures 4 and 5 one of them, illustratively member Hi2a,

is shown on an enlarged scale. The electrode member is preferably formed as a piece of hollow conductive tubing having an upper open end portion ll3a, the topof whichis cut to provide an outwardly extending fin IMa (see Figure 5), the purpose of which is to scoop in air and direct it down through the tip member, as will more fully appear hereinafter. Electrode member M2 terminates in a lower restricted portion Hita.' Interfltting with this restricted portion i 958 is a tubular jacket HSB (shaped as shown), removably interlocked therewith as, for example, by

means of a bayonet joint indicated clearly in Figures 4 and 2.

I'he electrode members M2 .are preferably made of a material, such as aluminum, which is a good conductor of heat as well as electricity and which may be simply and economically produced. The above-described construction lends itself to rapid and economical manufacture.

The tubular jackets are subjected,ras will later become clean-to the electric discharge emanating from its lower outer surface portion or the tip end z. Such electrical emanations cause heating, burning and other deteriorating eects unless` adequately safeguarded against. To withstand the heavy duty imposed upon the lowermost end portions of the electrode tip members, the tubular jackets are preferably made of a conductor, such as steel, which can withstand the electric discharge emanating from its lower outer surfaceI without undue deterioration and yet which lends itself to rapid and economic production.

In Figure 2, the inclined positioning of the electrode member lf2, and the others as well, with respect to the fianged or skirt portion iii of the rotatable housing 80 is shown. The electrode housing is driven in such a direction as to cause the electrode members H28, H2", H2c, etc. tovmove through the surrounding atmosphere with their upper end portions H33, H3b, H32, A

etc. leading and their lowermost tip portions e trailing. As may be seen from Figure 5, the electrode members are cylindrical in form, and as positionedin Figure 2, a horizontal cross-section of the electrode member is substantially elliptical outer rotatable housing 8U. The outer periphery of the portion I2| is provided with a circle of holes which are adapted to receive the upper end portions of electrode members |25 which are thus arranged in a circle, being also inclined, andare preferably slanted in a direction opposite to that of the electrode members I|2a, Il2b', IIZC, etc. on the other housing. To simplify construction, the electrode members |25 are preferably identical to the members II2, the details of which have been shown and described above in conjunction -with Figures 4 and 5. The electrode housings 80 and |20 with their respective electrode members II2, I|2b, etc. and |253, |25, |256, etc. are adapted to rotate in opposite directions, the purpose of which will appear more fully hereinafter, with their several respective extreme tip endy portions z of the electrode members trailing.

Upon'rotation of the ring of outer electrode members I2?, |I2b, II2C, etc., their respective leading upper end portions H31, H3", II3, etc., havingI respective air ns I |4a, etc., air is scooped in by the various fins above-mentioned and is directed down through the hollow or tubular electrode members and out through the extreme open end portion of their respective jackets Illia, IIS", H6, etc. Upon rotation of the ring of inner electrodes |25a, I25b, I25, etc., their respective leading upper end portions |2611, I26b, |260, etc. having respectivelyair fins |213, etc. air is scooped in by the latter fins and is directed down through the respective hollow or tubular electrode members and out through the extreme open end portion of their respective jackets |283, |20b, |28, etc.- The stream of air passing downwardly through the various electrode members serves t give a cooling effect whichaugments that produced by the rotation of the ring of tip members. This cooling effect contributes toward negativing the tendency of small particles of metal to separate from the electrode members, particularly from the tip portions z, and hence contributes toward keeping thetreatment zone free from such metallic particles.

In addition to the above-mentioned cooling effect, the circulation of air about the electrode members, due to their rotation, Aand the additional air circulated due to the current of air flowing out of the electrode members contributes toward blowing away from the treatment zone, or space between the electrode members and the belt, any small particles of metal coming 01T from the electrode tip members and thus prevents the establishment and maintenance of a dynamic arc. Thus the air circulation means employed directly contributes toward maintaining the treatment zone free from extraneous electrical effects which would tend to decrease the efficiency of treat-` ment, detract from the dependability of operation, and which might generally impair the eflciency of the treating apparatus.

As is better shown in Figure 2, the holes in which the electrodes I|2 and |25 are seated are formed in the thickened peripheral portions of the above-mentioned skirt portions III and |2I, x

respectively, the above-mentioned air fins resting against the upper face of these peripheral portions thus limiting or ixing the position of the electrodes and .thus'insuring that the active tip ends z thereof fall in the same plane. The electrodes I2 and |25 are held in their respective holes each by a set screw 49, and the upper ends of the electrodes |I2 and |25 Vmaybe covered over by ringlike plates 50 and 5| secured respectively to the extreme peripheral or flange portions of the portions III and I2I, respectively. Thus, the as-` sembly and positioning of the electrodes relative to their supports may be readily and quickly achieved and is, moreover, highly dependable.

For illustrative purposes, the outer electrode housing 80 with its associated electrode members I2 may be drivenat a speed of 1200 R. P. M. and the inner housing |20 with its associated ring or circle of electrode tip members |25 (having a smaller diameter) is driven at a speed of approximately l1300 R. P. M. With the relative dimensions of the circles formed by the outer electrode members I2 and the inner electrode members |25, as illustratively shown in Figure 3, the peripheral velocities of the two circles of electrode tip members is preferably substantially the same. With the same spacing between electrode members in the outer housing 80 and the inner housing |20, it will be seen that an article passing beneath the electrode structure receives approximately Vthe same number of impulses from each of the oppositely rotating sets of electrode tip members. Such a construction assures a more uniform treatment of the material, articles or other products undergoing treatment as will be more fully described hereinafter.

Considering now more in detail the construction of the driving means for the several sets of electrode members II2 and |25 above-mentioned, it is rst to be noted that I prefer to make the housings 80 and I 20 each in two parts, and for, convenience the construction of housing 80 may rst be considered, reference being made now to Figure 2 of the drawings.

One of the parts of housing 80 is the lower portion which comprises a horizontally extending disk-like wall BI)a from whose outer periphery the skirt portion III projects downwardly and outwardly and from whose peripheral portion there projects upwardly a cylindrical wall portion 8()b which is counterbored as at 80C to provide a recess or seat within which the rotor 25 of the motor that rotates the electrode-members II2 and which rotor will be more in detail described hereinafter, is seated, being made up preferably of laminations of suitable magnetic material.

The other part or portion of the two-part housing 80 comprises the upper hollow horizontal butr slightly downwardly and outwardly inclined top Wall portion 8|)d peripherally terminating ina downwardly directed cylindrical wall portion 80e shaped to seat upon the upper face of the cylindrical wall portion 80b of the other part of the housing 80, suitable screws 26 (Figure 2) securing the two parts together and, it will be noted, acting also to clamp or hold the rotor 25 rigidly in place.

The lower wall portion 80a (Figure 2) is counterbored as at 80f to provide a seatA for the outer race 211- of a suitable combined thrust and radial anti-friction bearing generally indicated at 21 whose inner race 21b is seated against a shoulder 28a ofv a vertically extending stud Intermediate'of the bearings 21 and 29 and similarly strung, as it were, onto the stud shaft 28. is the stator 30 of the above-mentioned motor and adapted to coact with `theabove-mentioned rotor 25. Certain features of the construction are described later but for present purposes it will suffice to say. that the stator 30 is made preferably of disk-like laminations of suitable magnetic material, suitably diametered to be received, ,with adequate clearance, within the annular rotor core 25.

Interposed between the stator 30 and the inner race 29b is a ring or spacer 3| and interposed between the stator 30 and the inner race 21b is a spacer 32, these lspacers vbeing likewise strung onto the stud shaft 28. The latter, just above the upper bearing 29, is threaded as at 28b to receive a threaded nut or collar 33, suitably apertured to be manipulated by a Spanner wrench, and when this nut 33 is tightened or driven home, the inner race 21h, spacer 32, stator core 30, spacer 3|, and the inner race 29b are securely clamped between the nut 33 and the shoulder 28a, thus dependably holding these parts in assembled relation. Accordingly, with the stud shaft 28 rigidly held in position, as is later described herein, the housing 80 with its rotor 25 and is depending electrodes ||2 may freely rotate about the stator 30 and the studr shaft 28.

The stator 30 carries appropriate windings 34, described in more detail hereinafter, and one terminal of the windings 34 is grounded as at 35 to the stator 30 and the other terminal is brought by a contactor 36 through a suitable aperture in the spacer 32 or in the stator 30 or both, and

thence through a radial channel 28C in the stud 28 and thence upwardly within the latter through an axially extending channel 28d.

The lower or inner electrode housing |20 comprises, as vabove noted, also two` parts; one of thesel comprises an upper disk-like and generally horizontally extending upper Wall portion |20a terminating about its periphery in a downwardly extending cylindrica1 portion |20b which is counterbored as at |20c to form a seat within which is received and seated the rotor 31, preferably built-up of annular laminations of suitable magnetic material. From the upper disk-like wallv portion |20.i the skirt portion |21, which carries the electrodes |25 above described, projects outwardly and downwardly under the cover of the skirt portion of the upper housing 80. The extreme peripheral or end portions of the parts and 12|, within which are the recesses for receiving the electrodes, terminate preferably in the same horizontal plane though they are' of sufciently diierent diameters to give the desired spacing between the two sets of opposite/ly rotating electrodes.

'I he lother part or portion of the two-part housing |20 includes a bottom closing wall portion |20d which extends in a rgeneral horizontal direction'though inclined somewhat upwardly (Figure 2) terminating peripherally in an up-y wardly extending cylindrical wall portion |20@ which mates with the end of the cylindrical wall portion 1201 closing the recess |20c in which the 31 is securely clamped or held in place.

The yinnermost portion of the upper wally por-y tion |20a is counterbored as atl |20bto receive the outer race 39a of a combined thrust and radial bearing4 39,- whose inner race 39b is snugly fitted to the lower portion of the stud 28 but which abuts against the shoulder 28a abovementioned. v

The lower or closed Vwall portion |20d is counj wrench, or the like.

terbored as at. 120 to receive the outer race 40a of a combined radial and thrust anti-friction bearing 40, whose inner race 40h is snugly tted onto the cylindrical part of the stud 2B.

Intermediate of the bearings 39l and 40 and also strung onto the shaft 28 is the stator 4|, also preferably laminated and hence made up of suitable sheets ofmagnetic material, such as transformer iron, but with a collar or spacer 42 between the stator 4| and the inner race 39b anda collar or spacer 43 between the stator 4| and the inner race 401.

The lower end portion of the stud 28 is threaded, as at 28e, to receive a nut or collar 44 suitably apertured to be operated by a spanner Between the nut 44 and the shoulder 28a on the stud 28 the inner race 39h, the spacer 42, the stator 4|, the spacer 43, and the inner race 4|)b are securely clamped and held in assembled relation.

The stator 4| is provided with windings 45 one terminal of lwhich is grounded as at 46 and the other terminal of which is carried, as by conductor 41, through an appropriate aperture in the spacer 42 into` a radial channel 28f in the stud shaft 28 and thence upwardly in the channel 28d where the conductor is joined to the above-mentioned conductor 36 which'merges from the channel adjacent the upper endof the stud 2B by way A Thus, the lower or inner housing |20 with its electrodes |25 is mounted for free rotation coaxially with the upper or outer housing 80, the electrodes and theirvdriving means forming a compact unit which vmay be fixed in position by appropriately securing the stud shaft 28 to a suitable support, The operatingfparts of the motor or motors are dependably encased and if desired further security of enclosure may be achieved by interposing felt or similar washers 48, seated in appropriate recesses in the hub portions of the casing parts d and |20d, between the latter and the collars 33 and 44, respectively.

The induction motors within the housings 80 and |20 are preferably constructed to operate at commercially available frequencies, such as 60- cycle alternating current energy and may be constructed to operate at a voltage on the order of volts or. 220 volts. The motor within the housing 80 is constructed as a six-pole motor giving a speed of rotation of the housing 80 and hence the electrodes |I2 of 1200 R. P.' M. The diameter of the circle of the electrodes |25 carried by the housing |20 is less than the diameter of the circle of the electrodes H2 and, to give substantially the same linear speed thereto, the motor within the housing |20 is constructed as Aa four-pole motor which, at 60 cycles, gives a secured to the beam 82, which may be metallic, rotor 31 is seated and, when the two parts areMJ secured together as by thescrews 38, the rotor by suitable socket-like brackets 52 and 53 (Figure 1). The conductors 36 that come up through the stud shafts 28 (see Figure 2) may be connected to a common conductor 54 that leads to one side of a suitable source of power current,

.suci as 60-cycle alternating current energy, and

grounded as was above described in connection with Figure 2, thus completing the supply to the windings of the motor or motors of the driving energy.

The electrodes ||2 and |25 are maintained at a high potential, a potential on the order' of 150,000 volts, preferably alternating and preferably of relatively high frequency, a frequency, for example, on the order of 640 cycles per second. This potential is supplied by a low voltage high frequency alternator 51 supplying energy to a step-up transformer Sli-59, one terminal of the high voltage winding 59 of which is grounded to the frame of the machine as at 60 and the other terminal of which is connected to the supporting beam 82, as by way of the conductor 56. The transformer 55, in this case, is insulated to withstand this high voltage and thus safely to protect the low voltage side and circuit of the transformer 55 against this high voltage. The electrode structures S and T being grounded to the beam 82 or mechanically and electrically connected thereto, are thus maintained at this'high potential. f

The beam 82, thus also at high potential, supports the structures S and T so that the planes of their electrodes are parallel to the plane of the product-carrying side of the belt Il and is movably supported by the main frame l for adjustment thereof and hence of the electrode structures S and T toward or away from the belt A possible form of adjusting or elevating mechanism is indicated in Figure l and it may include the manually controlled elevating screws 6| and 62 whose threaded brackets 53 and 64 are connected to the high potential structure or beam l82 through insulating frames 65 and 56, respectively.

Cooperating with the electrode structures S and T and spaced immediately beneath the upper part of conveyor belt and the insulating sheet 20, there are arranged, preferably in the form of two cylindrical groups |4| and |42 (see Figure l) substantially coaxially with the electrode structures S and T respectively, a suitable number of preferably identical electronic conduction devices |43. The extreme outside diameters of the cylindrical groups |4| and |42 of these conduction devices are preferably equal to or slightly less than the diameters of the circles traced by the extreme tip portions of the outer rings of electrodes l2 of the electrode structures S and T, where the latter.

take the form described in connection with Figures 2 and 3, as they are whirled above the conveyor and the product to be treated. The inside Y diameters of the cylindrical groups |4| and |42 of these conduction devices are substantially equal to or greater than the diameters of the circular paths traced bythe extreme tip portions of the inner rings of electrode members |25 of the electrode structures S and T, respectively.

Preferably, the electronic conduction devices |43 are in the form of elongated cylindrical tubes of diameters substantially equal to the distance between the centers of the inner and outer electrodes ||2 and |25, andof such ,length that they are adapted to be conveniently received within the space between the upper and lower sides of belt l1; illustratively the length is five or six times the diameter.

The various electronic conduction devices |43 are maintained in cylindrical groups |4| and |42 spaced from electrode structures S and T respectively, as indicated above, by suitable racks |44 and |45. and their associated supporting yokes |46 and |41, respectively, preferably bolted to the side wall portions 2| and 22 of the conveyor belt supporting framework (see Figure l) For reasons of simplicity and economy of construction, the cylindrical groups |4l and |42 of like electronic conduction devices |43 and their associated supporting structures |44- |46 and |45- |41 are preferably identical so that but the one group |42 and the supporting structures |45-|41 is considered in detail.

Referring now more particularly to Figure '7 there is shown at |45 a circular rack preferably rotatably mounted and including illustratively a.

flat dish-shaped cast aluminum base |48 having a central hub portion |48a and an outer upturned `rim portion |48b, the outer periphery of which is provided with raised circumferential sections |42!c and |48d to form a sheave, the purpose of which will appear more fully hereinafter.

Preferably made integral with the base |48 and spaced adjacent and including the outer upturned rim |48b thereof, are a number of individual socket wall portions |48e which are adapted to receive the lower ends of .electronic conduction devices |43 comprising the cylindrical group |42. 'I'he interior of the various sockets |48e is preferably enlarged and adapted to receive a ring |49 of yieldable material, such as feld or rubber, the upper edge of which contacts the lower edge of the inwardly extending rim |48f or reduced section of the socket which loosely receives an electronic conduction devicel |43. The ring |49 is forced upwardly against th'e inwardly extending rim |48f by a metallic circular band |50 which is loosely received within the socket and which is held in position by a cup-shaped end-cap |5| threaded in the lower slightly enlarged interior of socket |488.

Each electronic conduction device |43 preferably includes a cylindrical thin-walled glass envelope |52, the upper closed end of which is dented in or recessed as at |529' lending strength and rigidity to the end closure. Sealed intothe lower end |52b of the glass envelope and preferably axial thereto is an electrode |53 having an enlarged metallic head portion |53a and a downwardly extending stem portion |53b of reduced size. The electrode |53 is partially supported by wires |54a and |54b in their associated supporting ring portion |54c conveniently sealed into the protruding end portion |52b of the glass envelope.

The glass envelope preferably contains one of the noble gases, such as neon, at a pressure of illustratively 6 millimeters of mercury which is adapted to be ionized and rendered highly conductive when subjected to a suicient high electrical potential gradient, as will more fully appear hereinafter.

The electrode stem |53b projects through a small hole portion |5|a provided in the end cap |5| whereit is bent over and fastened to the end cap by a suitable screw |55 after the electronic conduction device is properly positioned within the socket.

In positioning the electronic conduction device in its socket so that it is firmly held against lateral displacement in spite of slight shocks and jars that may be encountered in actual use, ring |49 of yieldable material is expanded in a radial direction so as to tightly press against the wall of the electronic conduction device adjacent its lower portion by screwing up end cap |5| and forcing the circular band |50 to compress the ring |49 in an axial direction.

Ans

To maintain the various electronic conduction devices kM13 in upright positions with their axes parallel to the central axis of the cylindrical group |92, a short insulating tubular section |56.

n preferably of a material such as Dilecto or lam- ;inated Bakelite having high electrical insulating properties .coupled with mechanical strength, is axially mounted on hub |63a of the base plate |68 and supports the l flat circular disk |51 `(in a plane substantially perpendicular thereto) of insulating material, such as Diletco or laminated Bakelite, the central portion ofl which is recessed Vas at |51a and adapted to snugly fit a reduced end section |56a of lthe central tube |56 and be fastened thereto by a suitable-pin or set screw A. |58. The outer rim of disk |51 is provided with a suitable number, of spaced hole portions |51b which are adapted to snugly receive the upper -of base plate |68.

s end portions just clear the lower surface of the s olid dielectric plate 20 supporting the upper part of theI conveyor belt I1 within the region immediately beneath electrode structure S or T. They are maintained in this position by the stem portion or terminal |53b of the electrode which, as above-mentioned, is brought out and fastened to the end cap |5|. The electronic conduction devices are further held in proper position as above-mentioned by the gripping action of the yieldable rings |49 included within each socket.

Rack |65 with electronic conduction devices |63 arrayed in a cylindrical formation about its outer portions, is preferably rotatably mounted on a short upstanding shaft |62, the lower end of which is received within the central portion |61.a of an H-shaped yoke, preferably of cast aluminum. The H-shaped yoke is also provided with arms |ll1b, the ends of which are illustratively crooked upwardly and bolted to thelower edges of the insulating side membersZl and 22 of the conveyor belt supporting structure 2D, etc. The

central portion of yoke |131a is preferably pro vided with a raised collar |61c integral therewith, upon the upper edge, of which rests a shoulder ,portion |62P of the shaft |62; permanent connection between shaft and yoke being achieved preferably by horizontal pins |63.

Shaft |62 is provided with an upper reduced portion |62b which receives the inner race |64a of the upper ball bearing assembly |615 preferably of a semithrust construction.. The inner rac'e is secured to the shaft by a nut |65 which holds the race against a shoulder portion |62c of the shaft. The outer race |66b of the ball bearing assembly is received within a recessed portion Illg of the hub portion MGS of base plate |68 and is maintained securely therein by end cap |66 which threadedlyengages an upper interiorly-threaded portion of hub |68a. End cap `|66 is interiorly cupped so yas to permit free movement with respect to nut |65 and the upper end of shaft |62. Shaft |62 is provided with an additional reduced portion |62d upon which is mounted the inner race |61a of the ball bearing assembly |61 in a pressedfit relation, the outer race |61b of which is tightly more particularly described above.

*aisavos received within a recessed portion 168k of the hub portion ldaof base plate M8.

Ball bearing assembly 61 preferably has semithrust characteristics and sustains part of the weight of the array of electronic conduction devices and their supporting rack M5; the upper end of recessed portion M311 resting directly on the upper edgeY of the outer race |611 of the lower ball bearing assembly. Lower ball-bearing assembly |61 is preferably rendered dust-tight and greasetight by a dust ring |61c preferably including a felt ring, the inner periphery of which rides upon the outer periphery of the inner race |611a of the ball bearing assembly, and the outer periphery of which is preferably received withinv a recessed portion of the outer lrace |61b and maintained tight in this position by a spring ring seated within a circumferential groove.

Thus, the cylindrical array of electronic conduction devices is securely supported'and adapted to be rotated about an axis coincident with the axis of rotation of an electrode structure and with the extreme upper ends of the electronic devices moving in a common plane substantially parallel to that of the extreme tip portions of electrode members ||2 and |25 and to the upper conveying surface of belt l1.

'It may at this point be noted that the abovedescribed rack and rotatable mounting therefor permits a maximum length of electronic conduction device between upper and lower sides of belt I1, or fora desired size and length of electronic conduction device enables a minimum size of driving and driven pulleys I5 and |6, respectively; the lower side of belt |1 passes in a return direction just clear of the lowermost portions of the supporting yoke |61'to permit a generally compact and rigid construction which, furthermore, is extremely light in weight and well adaptedto be' supported by the light insulating conveyor belt supporting structure.

As mentioned above, the cylindrical array IM of electronic conduction devices |63 mounted in rack |44 and supported by yoke |66 are preferably of identical construction to the cylindrical array of electronic conduction devices |63 mounted in rack |45' and supported by yoke |61, all as The electronic conduction devices or gaseous conduction devices thus constructed are preferably rotated in` opposite directions conveniently l by an electric motor |68 illustratively of the single phase induction type which is conveniently bolted to an outwardly projecting arm portion ||e preferably made integral with the upstanding support ll. l

Mechanical driving energyv is conveniently transmitted to electronic conduction device rotor assemblies l|lH-|4l l66 and |42-|45-|41 by a belt |69 of high electrical insulating characteristics, such as a cotton fabric', which is received within sheaves or circumferential groove portions of racks |44 and |45, the detailed construction of which is more particularly set forth above, the belt preferably crossing over at a point t between the rotor assemblies so as to rotate them in opposite directions.

Motor |68 is preferably driven (upon being energized in a manner described more fully hereinafter) in a counter-clockwise direction, looking downwardly on the motor as seen in Figure 1, and transmits motion by belt |69 to electronic conduction device rotor assemblies ll-lM-lll and |42|65|111 in ccunterclockwise and clockwise directions, respectively. l.

The rotation of the electronic conduction device rotor assemblies is preferably relatively slow giving them a peripheral velocity of about 500 feet per minute. The advantages of rotating the electronic conduction device rotor assemblies will appear more fully hereinafter in considering certain electrical actions and effects on the product to be treated as it is conveyed through the region between the rotating electrodes maintained at a high electrical potential and their respectively associated electronic conduction device rotor assemblies.

KUnder operating conditions of the treating apparatus electronic conduction devices |43 become ionized, in a manner more fully described hereinafter, and emit a dull red-orange glow (for neon) indicating that the tube is functioning properly. In order that the devices may be observed, the downwardly extending side members 2| and 22 of the conveyor belt supporting structure are provided with apertures (not shown) adjacent electronic conduction device rotor assembly |4| |44|46 (see Figure 1) and apertures 2|c and 22 (Figure 7) adjacent electronic conduction device rotor assembly |42-|45-|41.

A defective electronic conduction device may be readily detected by an absence of the abovementioned glow of the device and a replacement of the defective electronic conduction device may then be made. `In effecting the replacement of an electronic conduction device |43, the edge of the lower side of conveyor belt |1 immediately beneath the defective device is pushed clear of the space immediately `beneath the particular socket supporting the defective device; the belt being of such length and physical characteristics as to pernut the distortion indicated.

End cap |5| associated with socket Hlth-|48e (see Figure 7) holding the defective device |43 is then unscrewed from the lower portion of the socket and tube |43 is withdrawn or pulled down through the socket and taken out beneath the conveyor belt supporting structure, sufficient working space being provided between the arms of yoke |41. A replacement of the defective electronic conduction device is effected in a substantially reverse order, care being taken, as mentioned above in connection with the initial mounting of the electronic conduction devices in their respective sockets, that the upper end of the replaced device be properly spaced from the solid dielectricsheet 20. Thus, a defective conduction device may be readily detected and quickly and 'effectivelyreplaced with a minimum expenditure of eifort and with a minimum shut-down of the apparatus, all with a minimum change, alteration or disturbance of other p arts of the apparatus. .y

As mentioned above, the lower base plates of the racks supporting the various electronic conduction devices are preferably made of metal, as well as the supporting shafts, bearings and yokes, so that paths of good electrical conductivity are provided from the various electrodes of the electronic conduction devices, through the parts above-mentioned including the electrically conductive metallic end caps to which the electrodes are directly connected.

Referring to Figurejl, desirably underneath conveyor belt |1 are positioned two condenser plates 61 and-68. In this embodiment these plates arf,` made of sheet metal and have a dimention crosswise of the `belt in excess of the widthof the belt itself or the width of the plate 26. The lengths of the condenser plates 61 and 68 quency are somewhat in excess of the respective lengths of the treatment zones along the belt; preferably the condenser plates 61 and 68 are made substantially square (see Figure 6).

The condenser plates 61 and 68 are preferably mounted in a common plane, the plane of each being substantially parallel to that of the tips of the electrode structures S and T, respectively,

l and the plates are mounted in any suitable manner so that they may be moved in a vertical direction and without being shifted in their axial relation with respect to the electrode structures S and T. An illustrative form of mounting is shown in Figure 1 and it will be seen to include a cross-beam support 69 upon which the plates 61 and 68 are directly mounted. The member 69 is preferably of such a material, for example iron or steel, which lends suitable mechanical support to the condenser plates 61 and 68 and which also serves as an electrical conducting member between the plates and the frame. The cross-beam 69 includes the threaded brackets which respectively engage suitable elevating screws 1|] and 1| suitably journalled in standards and l2.

The elevating screws 1li-1| may be conjointly controlled as by a hand-wheel 12 suitably geared to the screws, as shown in Figure l, and thereby the condenser plates 61 and 6B may be positioned appropriately with respect to the electronic conduction devices above described and also with respect to the electrode structures S and T.

The product to be treated, illustratively our, milled cereal, or the like, and illustratively packaged and hence indicated at C in Figure l, is, as above noted, moved by the conveyor l1 ina direction from the left to the right and hence it enters 'rst the treatment zone under the electrode structure S and then the treatment zone under the electrode structure T, a corona-like discharge emanating from the tips z of the oppositely rotating rings or circles of electrodes ||2 and |25 (see Figures 2 and 3) in each ofthe electrode structures S and T, accompanied by actions already briefly described in connection with the structure of Figure 2; this corona-like discharge impinges .upon the belt I1 or upon the dielectric plate 2U that supports the belt, and due to the number of the electrode members and their relatively high rate of movement, as well as due to the high freof the potential applied to them, the corona discharge that emanates from each circle of electrodes is in the form substantially of an annulus of 'innumerable and apparently dense mass of fine corona streamers. The lower portions of these annuli are controlled and prevented from spreading or straying by the action of the electronic conduction devices M3 above described, the action of which, moreover, due to their movement or rotation as above described, is uniformly distributed throughout the general circle `whichtheir upper ends dene. Y

This action is important in achieving rapid and eiiicient sterilization. When a product which is being treated is passing through the treatment z one the' concentration of flux and the movement of the electrodes results in thorough sterilization of the product. 4As will be explained below in connection with Figures 8 and 9, the corona discharge is directed to every portion of the article as it passes through the apparatus.

vIn the above-mentioned annuli of concentrated local rupture or corona discharge, the articles or materials to be treated are moved by the continuously moving belt |1. The material, having a higher average permittivity than the air dielectric through which the local rupture had been taking place, brings about a redistribution of the voltages in the paths leading from the electrode tips H2 and ,S25 to the condenser plate 'l (or t8) and in fact causes a, still greater and more intense concentration of the local rupture and also an earlier rupture (because it is made to occur at a lower point on the voltage wave) than had been previously taking place.

The air dielectric intervening the spaces in the particles of the material, such as the grains of corn meal, is quickly ionized and is, in fact, overstressed to a greater extent than the air dielectric between the electrode tips z of electrodes H2 and E25 and the plate 2@ because of this in.- tervening air dielectric having a low permittivity, namely unity, while the average permittivity of the individual particles of the material'is higher than that of, air. Hence the local rupture or corona takes place within and throughout the material and; because the contaminating insect life has a substantially innite permittivity and is in eect electrically conducting, this insect life is sought out by the corona streamers which pass therethrough and thus bring about its destruction.

The uniform currentdensity, toward the achievement of which the electronic conduction devices 463 contribute, aids materially in achieving eective and uniform destruction of insect life.

If the material is packaged as, for example, in pasteboard cartons or packages, the above-described actions likewise take place but are accompanied by a further action which prevents puncturing of the material oi the carton. The pasteboard or paper or like material of the package. has an average permittivity that is higher than the air which, prior to the entry of the package into the treatment zone, constituted the dielectric between the electrode structure S (or T) and the plate 2li (see Figure 1). More particularly, the walls of the carton or package act as condenser dielectrics which become serially related with the dielectrics of the fixed and variable capacities otherwise in the circuit. The resultant redistribution of voltages throughout the thus 'i to newly and serially related condenser dielectrics is such that the voltage gradient across the material of the carton is below ,the puncturing gradient and hence puncturing of the material of the carton is positively precluded.

The solid dielectric (member 2h) of the above-- mentioned ixed capacities also functions to protect the electronic conduction tubes M3 against punctureof the glass envelopes thereof and I am thus enabled to avoid the disadvantages that might accompany the use of electronic conduction devices of otherwise adequately thick walls. In the absence of such protective means,` the walls of the tubes M53 would have to be made relatively very thick with the result that it would be dimcult to achieve a sumcient homogeneity of current density at the bottom of the corona annuli because in turn the gas columns could not be suiciently closely spaced.

Another action that comes into play and con-` tributes toward the achievement ofthe above- :described results and advantages is the condenser action between the plate memberswmilkandtl (Figure l) in the circuit of the treatment zone under electrode structure S; and between the plates iti? and td in the circuit of the treatment 'I zone of the electrode structure T; these `are virtually air condensers and they are dimensio'ned,

v 55 as by maintaining the spacings `between the plates thereof sumciently great, so that each of itself can withstand the total or maximum high potential of its own circuit without breakdown or rupture, and thus spark-over or complete rupture in the circuit of either electrode structure S o-r T is prevented. Furthemo're, by varying the spacing of the rotating electrodes from the' belt H, I may control theintensity of the individual corona streamers to suit them to the particular conditions to be met with in practice.

But an action comes into play because of the character and/or movement of the corona streamers emanating from the two oppositely moving or rotating sets of electrodes H2 and 25, this action being identical in the two structures S and 'I' and repeated; in fact, because of this feature of action, Iam enabled to dispense entirely with one treatment zone and hence utilizing only one electrode structure (S or T) with Y the corresponding control means, such as only one Vcylindrical group Ml of tubes M3 and one condenser, such as the air condenser formed between the parts H38 (Figures 7 and 1) and the condenser plate Si. In Figures 8 and 9 I have diagrammatically shown, by circles made up of arrows, the directions of movement of the sets of electrodes i l2 and l25, and four successive positions of the same package C as it is moved in the direction from A to B and hence from left .to right.

,Because of the tendency of the corona discharge emanating from the moving electrodes of the structure S (or T) to persist particularly along the outside surfaces of the side or end walls ofthe package C when, due to the direction of movement of the electrodes, the discharge is moved, as viewed in Figures 8 and 9, toward the package, and because of flux refraction and like factors brought about by the action of the paper or pasteboard or like dielectrics of which the carton is made, thereis a tendency for the corona discharge not to take place in regions of the material within the package closely adjacent to that exterior side or end wall of the pakage' onto which the discharge has just been wiped or swept. f v For example, at the left of Figure 8 note how the electrodes M2 sweep lthe discharge downwardly (as viewed in that figure) with respect to the upper side wall; accordingly, there is a region or portion of the material adjacent that side wall that is likely to be insuiiiciently treated, but in the region adjacent the lower side wall of the package in the left-hand positionl in Figure 8, that action does not take place and the material is thoroughly sterilized.

Howeven as the package continues to move from the left to the right, it strikes the oppositely moving eiects of the inside ring of electrodesmfand the discharge from the latter acts in a reversed manner, namely, while it may not thoroughly act upon 'the material adjacent the lower side wall of the package (that being now not necessary since that portion was thoroughly treated by the ring of electrodes H2) it does, however, completely permeate and penetrate all `portions of the material adjacent the upper side wall (the portion or region that was'likely to be o Yinsufiiciently treated by the discharge from the electrodes M2). l

As the package continues to move toward the right and progressively into and through the right-hand portion of Figure 8, these actions are again reversed, and thus double certainty of comthat similar actions as above described take place with respect also to the leading and trailing vertical or end walls of the package. Figures 8 and 9, therefore, indicate diagrammatically successive positions of the same package with respect to the oppositely moving concentric rings of electrodes and show how the possible deciencies of one s et of electrodes with respect to material immediately inside of a particular vertical wall of the package are remedied by the action of the other of the concentrically moving electrodes.

As all these actions take place, the air being scooped up by the vanes I i4 (Figures 2, 4 and 5) is projected downwardly through the orifices or nozzles H, not only -with actions already above described, but also thereby blowing out of the treatment zone ionized air or air remaining ionized when, in a voltage wave or pulsation, the instantaneous discharge has ceased. This action l is important because it makes sure that, upon the next voltage wave or impulse, the local rupture or corona discharge takes place on a higher point of the voltage wave.

As earlier above noted. various forms of electrode structures may be employed and I have pointed out how, withv the unique arrangement of Figures 2 and 3, I may utilize only one treatment zone instead of the two, as shown in Figure 1. However, I may achieve other advantages and results of my invention by using for the electrode structure S only one of the rings of electrodes of Figures 2 and 3 and its corresponding motor drive. In such case I employ two electrode structures S and T, but drive them in opposite directions, thereby providing two laterallyspaced treatment zones in which the actions, with respect to packaged material, are reversed and thus complete sterilization insured.

'I'he Ywindings of the motors employed in the structure shown in Figure" 2 may take the form shown in Figures and l1 in which the stator is, as above noted, slotted to receive the various coils WI, W2, W3, W4, etc., connected serially and also to the other circuits, as already above described. The rotor may have a winding of the sguirrel cage type, known in the art, and indicatedin Figure 10 by the cross-conductors K connected to the spaced rings P (see also Figure 2). The periphery of the stator may also be slotted and set into the slots, closed circuit coils X (Figure l1) acting as shading coils to give the motor appropriate starting characteristics.

The rotating cylindrical groups Uil and M2 of conduction `tubes M3 coact in achieving the above-described actions of the rotating electrode structures S and T and coact also in achieving the results .above described in connection with Figures 8 and 9. They insure uniform density of discharge in the treatment zones and also uniform distribution of the corona streamers throughout the annulus or annuli of discharge emanating from the rotating ring or rings of electrodes.

. It will thus be seen that there has been provided in this invention an apparatus in which the various objects above described, together with many thoroughly practical advantages, are successfully achieved.

' As many possible embodiments may be made of the above invention and as many changes .might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings, is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In electrical treating apparatus of the type wherein a high potential is impressed across a pair of electrodes to produce discharges within a treatment zone, in combination, a source of high potential, capacity-forming means connected thereto and including two opposed rotating electrode means having adjacent eiective discharge-controlling portions of substantially matching effective area with a treatment zone therebetween, one of said electrode means comprising two coaxial electrode members rotating in opposite directions, and means for moving a product through said treatment zone.

2. In electrical treating apparatus of the type wherein a high potential is impressed across a pair of electrodes to produce discharges within a treatment zone, in combination, a source of high potential, capacity-forming means connected thereto and including two opposed rotating electrode means having adjacent eiective discharge-controlling portions of substantially matching effective area with a treatment zone therebetween, Aone of said electrode means comprising two coaxial ring-like members, each having a plurality of discharge electrodes directed toward the other electrode means, means for rotating said ring members in opposite directions, and means for moving a product through said treatment zone.

3. In electrical treating apparatus of the type wherein a high potential is impressed across a pair of electrodes to produce discharges within a treatment zone, in combination, a source of high potential, capacity-forming means connected thereto and including two opposed rotating electrode means having adjacent eiective discharge-controlling portions of substantially matching -effective area with a treatment zone therebetween, one of said electrode means comprising two oppositely rotating electrode members, and the other electrode means comprising electronic conduction means, and means for moving a product through said treatment zone.

4. In electrical treating apparatus, in combination, a source of high potential, capacityforming means connected thereto and including a movable electrode structure and means juxtaposed thereto for coaction therewith for producing an electric discharge within a treatment zone, means for moving a product through said treatment zone, said electrode structure having a discharge electrode and means responsive to the movement of said electrode structure for effecting a blast of air current lengthwise of said electrode.

5. In electrical treating apparatus, in combination, a source of high potential, capacityforming means connected thereto and including a movable electrode structure and means juxtaposed'thereto for coaction therewith for producing an electric discharge within a treatment zone, means for moving a product through said treatment zone, said electrode structure having a tubelike electrode and vane-like means responsive to movement of said electrode structure for scooping air into said discharge electrode.

6. In electrical treating apparatus, in combination, a source'of high potential, capacity-forming means connected thereto and including a movable electrode structure and means juxtaposed thereto for coaction therewith for producing an electric discharge within a treatment zone, means for moving a product through said treatment zone, said electrode structure having an electrode projecting therefrom and said electrode having an eiective discharge-emanatingportion removably secured thereto.

7. An apparatus like that of claim 1 in which there are means for moving ionized air out of the discharge zones.

8. An apparatus like that of claim 1 in which the two coaxial electrode members are carried respectively by motive means, the rotating elements of which rotate in opposite directions.

9. An apparatus like that of claim 1 in which the two coaxial electrode members are carried respectively by two rotating housings, one of which is reentrant and receives therein the other, and means within the housings for eiecting their rotation.

10. An apparatus Ylike that of claim 1 in which the two coaxial electrode members are rotatably supported by a common stationary support, the latter'carrying driving means effecting opposite directions of rotation of said coaxial electrode members.

`11. An apparatus like that of claim 1 in which the coaxial electrode members rotate about a common stationary support, and means rotatably supporting them with respect to said support.

12. An apparatus like that of claim 1 in which the coaxialelectrode members are supported by a common supporting means, the latter carrying the stationary elements of two motive means, and rotatably supporting the rotatable elements of said motive means, and means connecting the` rotating elements respectively to said electrode members.

13. An apparatus like that of claim 6 in which the removable portion is secured to the electrode by a bayonet joint.

14. Anl apparatus like that of claim 6 in which the electrode structure is of sheet metal tubing.

15. An apparatus like that of claim 6 in which the discharge-emanating portion is made of sheet metal. o

16. An apparatus like that of claim 3 in which the electronic conduction'means has an eifective portion juxtaposed to the two oppositely rotating electrode members that deiines an annular area commensurate with the annular area defined by the rotating electrode members.

17. An apparatus like that of claim 3 in which the electronic conduction means comprises a plurality of electronic conduction tubes arranged substantiallyin a cylinder.

18. Inelectrode structure of the type used in treating apparatus, in combination', a stud-like supporting member having mounted thereon and spaced axially therealong two stationary elements of two motive means, two frame-like members each carrying a rotatable element for coac tion with one of said stationary elements of said motive means, thereby to complete the latter, means rotatably supporting said frame-like members from said stud-like member and for thereby positioning said rotary elements in coacting relation to said stationary elements respectively, and electrode means carried by each of said frame-like members at respectively diiferent distances from the common axis of rotation of said frame-like members.

19. A construction as lclaimed in claim 18 in which the' means rotatably supporting said framelike members is in the form of bearings alternated along said stud-like member with said stationary elements, said stud-like member carrying clamping means for clamping said bearings and said stationary elements therebetween and for therel I by securing them to` said stud-like member.

20. A construction as claimed in claim 18 in which one of said frame-like membersris reentrantand receives therein the other frame-like member, said electrode means on each being of substantially the same length, said frame-like members having means lying in substantially the same plane transversely to the axis of said studlike member for supporting said electrode means.

21. A construction'asclaimed in claim 18 in which the means rotatably supporting said frame-like members is in the form of a plurality of antifriction bearings having inner and outer races, said inner races being strung along said stud-like memberJ and alternated with said stationary elements of said two motive means, said oute races being respectively secured to said two frame-like members and said stud-like member carrying means for clamping said inner races` with said. stationary elements therebetween and for thereby securing them to said stud-like member.

22. A construction as claimed in claim 18 in which the two'motive means are electromotive means, the stationary and rotatable elements thereof having coacting windings which, when y energized from a suitable source of electrical energy, effect rotation of said rotatable elements vand hence of vsaid frame-like members with respect to said stationary elements, said stud-like member having extending therealong channel means, and electrical conductor means along said channel means and leading to said windings whereby, when said conductor means is connected to a suitable source of electrical energy, said windings may be energized.

23. A construction as claimed in claim 18 in which that motive means that drives the framelike member that carries the electrode means at a larger distance from the said common axis than the distance at which the other electrode means is carried by the other of said frame-like members is constructed to drive its frame-like member and hence its electrode means at a lower R. P. M. than the R. P. M. of drive of the other frame-like member by its motive means. I

24. A construction as claimed in claim 18 in which the said two motive means are in the form of alternatingA current induction motors, the respective stationary androtatable elements thereof carrying appropriate windings, the windings of that motive means that drives the frame-like member that carries the electrode means kat a `upon said shaft structure and adapted to rotate about a common axis, stator meansmounted upon said shaft structure, and independent rotor means associated with each of said electrode, structures 4and with said stator means to impart independent rotation to each of said electrode structures.

26. An electrical treating apparatus of the type wherein a high potential is impressed across a pair of electrodes to produce discharges within a` treatment zone, the combination of, a shaft structure, a plurality of motor-electrode structures rotatably mounted in alignment upon 'said' shaft structure, and electrode means carried by each of said motor-electrode structures, each of said motor-electrode structures including a casing shell enclosing a motor having a stator rigidly mounted upon said shaft structure and a rotor carried by said casing shell. i

27. In electrical apparatus of the type wherein a high potential is impressed across two electrode structures having opposed faces with a discharge zone between said faces, the combination of, an electrode structure positioned upon one side of the treatment zone including two annular electrode means mounted to rotate independently about a single axis, and means to rotate said two annular electrode means in opposite directions.

28. In electrical apparatus of the type wherein a high potential is impressed across two electrode means having opposed faces with a discharge zone between said faces, the combination of an electrode means including two electrode members mounted upon a single axis and means adapted to rotate said two electrode members in opposite directions -upon said axis, said lastnamed means including a nxed stator upon said axis and a rotor mounted upon one of said electrode members, said electrode means including a shell encasingsaid stator and said rotor.

29. In electrical apparatus of the type wherein a high potential is impressed across two electrode means having opposed faces with a discharge zone between said faces, the combination of an electrode means including two electrode members mounted upon a single axis and means to rotate said two electrode members in opposite directions upon said axis, said last-named means including a xed stator upon said axis and a rotor mounted upon one of said electrode members, said electrode means including a shell encasing said stator and said rotor, said electrode means adapted to cause air to circulate through said discharge zone.

FRANKLIN S. SMITH.

CERTIFICATE OF CORRECTION pei-.ent No. 2,152,705

r FRANKLIN s.

October ll 1958 SMITH.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring2 correction as follows: Page L first column, line 69, for the reference character l2Qb read lZOf;

page l0,

second columngline '(0, claim 26, for '.An" read In; and that the said Letters Patent should be read with this correction therein thatthe same may conform to the record of the c'ase in the Patent Office.

v Signed andV sealed this 29th day ofy November, A. D. 1958.

Henry Vari Arsdale 

